HTTP2 draft 13: support unknown frame types and settings types as extensions.

net/spdy/buffered_spdy_framer.h

Index: net/spdy/buffered_spdy_framer.h
diff --git a/net/spdy/buffered_spdy_framer.h b/net/spdy/buffered_spdy_framer.h
index 64aa0f786e04ba2d1a437f10b7dc9e3b5f77c632..426bc5ffb6e98f61437e46b85a6ba9599d359a79 100644
--- a/net/spdy/buffered_spdy_framer.h
+++ b/net/spdy/buffered_spdy_framer.h
@@ -81,7 +81,7 @@ class NET_EXPORT_PRIVATE BufferedSpdyFramerVisitorInterface {
   virtual void OnSettingsAck() {}
 
   // Called at the completion of parsing SETTINGS id and value tuples.
-  virtual void OnSettingsEnd() {};
+  virtual void OnSettingsEnd() {}
 
   // Called when a PING frame has been parsed.
   virtual void OnPing(SpdyPingId unique_id, bool is_ack) = 0;
@@ -103,6 +103,12 @@ class NET_EXPORT_PRIVATE BufferedSpdyFramerVisitorInterface {
                              SpdyStreamId promised_stream_id,
                              const SpdyHeaderBlock& headers) = 0;
 
+  // Called when a frame type we don't recognize is received.
+  // Return true if this appears to be a valid extension frame, false otherwise.
+  // We distinguish between extension frames and nonsense by checking
+  // whether the stream id is valid.
+  virtual bool OnUnknownFrame(SpdyStreamId stream_id, int frame_type) = 0;
+
  protected:
   virtual ~BufferedSpdyFramerVisitorInterface() {}
 
@@ -163,6 +169,7 @@ class NET_EXPORT_PRIVATE BufferedSpdyFramer
                                  size_t length,
                                  bool fin) OVERRIDE;
   virtual void OnContinuation(SpdyStreamId stream_id, bool end) OVERRIDE;
+  virtual bool OnUnknownFrame(SpdyStreamId stream_id, int frame_type) OVERRIDE;
 
   // SpdyFramer methods.
   size_t ProcessInput(const char* data, size_t len);